Blowing nozzles are used in a large number of applications in various industries. For example, compressed air and other gases emitted from blowing nozzles are typically used for cooling, cleaning, drying, liquid blowoff, material conveying, ejecting, and sorting tasks.
Although it is sometimes possible to use an open pipe to emit the compressed gases, it is usually advantageous to use a nozzle to reduce noise, energy consumption, and to increase worker safety. A variety of blowing nozzles are known in the art.
In many applications, the blowing nozzle must provide a certain minimum force to fulfill its function. For example, in a cooling, cleaning, or drying application, the blowing nozzle must exert enough force to reach its intended target. In a liquid blowoff, material conveying, ejecting, or sorting task, the flow generated by the nozzle must have enough force to move the material in question. For many nozzles, force can be increased by supplying compressed gases at increased pressures.
A frequent problem with blowing nozzles is gas consumption. The compression of air or other gases to supply the blowing nozzle requires energy and so a reduction of gas consumption often translates to energy savings, which in turn lowers operating costs. However, reductions in gas consumption are often accompanied by lower forces produced by the nozzle.
“Air amplifying” nozzles address gas consumption by entraining ambient air into the flow generated by the nozzle using the Coanda effect. This amplifies the flow produced by the nozzle. In some cases, the flow rate can be amplified by up to 25-fold by this effect. However, there is a persistent need to provide increased efficiencies with respect to the amount of ambient gases that can be entrained into the output flow of the nozzle.